Process for dyeing skins, hairs, and the like



UNITED STATES PATENT OSKAR KALTWASSER, OI? BERLIN, AND HANS OEHRN, OF BEBLIN-CHABLOTTENBURG. GERMANY, ASSIGNORS '10 ACTIEN GESELLSCHAFT Fi l TB, ANILIN FABRIKA'IION,

F BERLIN, GERMANY.

PROCESS FOR DYEING SKINS, HATES, AND THE LIKE.

No Drawing.

T 0 all 107mmit may concern Be it known that we, OSKAR KALTwAssER and Hans OEHRN, the first a citizen of the German Republic, the second owns no citizenship, residing at Berlin, Germany, and Berlin-Gharlottenburg, Germany, our P. 0. address being Urbanstr. 178, Berlin, Germany, and Mommsenstr. 13, Berlin-Charlottenburg, Germany, have invented certain new and useful Improvements in Processes for Dyeing Skins, Hairs, and the like, of which the following is a specification.

\Ve have found that the -nitro-2-amino- 1-oXyderivatives of the benzene series are excellently fitted for dyeing skins, hairs and the like morda-nted or not in the presence of a suitable oxydizing agent, such as hydrogen-peroxide. Thus are obtained yellow to brown dyeings of a great intensity and an excellent fastness to light.

The following example illustrates the inyention. without limiting it.

The skin to be dyed is washed for about an hour in water containing to grams of calcined sodium carbonate per liter, well rinsed and then dyed at ordinary temperature during 3 to 5 hours in a bath which rontains per liter 2 grams of 5-nitr0-2' amino-l-oxybenzene, 2 grams of ammonia of strength and grams of hydrogen peroxide of 3% strength: Then the skin is Specification of Letters Patent.

Patented May in, 1922.

Application filed December 7, 1921. Serial No. 520,696.

rinsed and worked up as usual. A clear yellow tint is the result.

011 skins previously mordanted with ironmordants yellow tints are also obtained; on skins mordanted with chromiumor coppermordants brown dyeings are produced. In

like manner substitution products of 5 nitro 2 amino 1 oxybenzene, such as its homologues, may be employed.

Having now described our invention and the manner in which it may be performed what we claim is 1. The herein-described process for dyeing skins, hairs and like materials which comprises treating the material in the presence of a suitable oxidizing agent in a bath containing a, 5-nitro-2-amino-1-oxy derivative of the benzene series.

2. The herein-described process for dyeing skins, hairs and like materials which comprises treating the 'mordanted material in the presence of a suitable oxidizing agent in a bath containing 5-nitro-2-amino1-oxybenzene.

In testimony whereof we aflix our signatures in presence of two witnesses.

Dr. Phil. OSKAR KALTWASSER. HANS OEHRN. lVitnesses:

I'IERMANN KIRoHHorr, FRITZ SOHILK. 

